Conventional vacuum degassing systems used for liquid chromatography are typically maintained at a constant vacuum level through use of a vacuum pump operating at a constant speed (revolutions per minute), operating by means that utilize feedback control or by cyclically applying a vacuum. The duration for which a solvent is present in the degasser is typically not constant due to changes in the flow rate of the solvent. Different types of solvents typically diffuse through the wall of the fluid channel within the degasser at different rates. Consequently, the different diffusion rates can adversely affect the measurement data obtain by the liquid chromatography system, for example, by introducing error to the composition gradient of a mobile phase.